Journal of Materials Chemistry C
·
2021
·Vol. 9
·期 44
·15910-15917
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IF 7.393
Zhen Wang,Yue Peng,Yongsheng Lu,Xiaosheng Tang,Xing Tan,Zhenshan Liang,Qiang Huang,Fei Qi,Nan Zhang,Weiwei Chen
With solution-processability, low-temperature proper energy level and superior stability, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is one common hole-transport material for the quantum dot light-emitting diode (QLED) application. However, the conductivity of the traditional PEDOT:PSS is very low, which has an adverse effect on QLED devices. Herein, one surface-annealing method for the PEDOT:PSS film to exchange their original composition and surface morphology is proposed. The advantage of this approach lies in the fact that the conductivity of the PEDOT:PSS film annealed with toluene (1.25 S cm−1) and ethylene glycol (EG, 10.52 S cm−1) are obviously improved compared with the air-annealing method (0.13 S cm−1). The difference is that the EG-washed PEDOT:PSS film shows a relatively rough surface with more PEDOT domains, whereas the toluene treated PEDOT:PSS film can promote the formation of a smooth, PSS-dominated surface and change the PEDOT chain structure from coiled to linear, thus, the conductivity of the PEDOT:PSS film is enhanced. As a result, the QLED device achieves a maximum luminance of 31 140 cd m−2 and power efficiency of 13.4 lm W−1, showing 48% and 25% enhancements, respectively, compared to the control device. This work provides an efficient approach for improving of perovskite QLED performance.
研究领域:
材料科学
·
电气工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Le Ma,Xiansheng Li,Xuehan Chen,Jingyu Li,Pengfei Liu,Changting Wei,Qingshan Ma,Leimeng Xu,Wenhua Zhang,Jizhong Song
Mixed halide CsPb(Br/Cl) 3 quantum dots (QDs) exhibit fine tunable blue light and narrow photoluminescence (PL) full-width at half-maximum (FWHM), which has attracted significant attention as a promising candidate to realize a new generation of blue light technology. However, the introduction of Cl − makes it very easy to be eroded by water in the environment, which will lead to deep-level defects and degrade the luminescence and stability of QDs. Here, we propose to introduce tetra- n -octylammonium oxalate (TOAOxa) to improve the water-resistance stability and exciton recombination of CsPb(Br/Cl) 3 QDs and QD-based light-emitting diodes (QLEDs). The oxalate ion (Oxa 2− ) of TOAOxa could form strong interaction with undercoordinated Pb 2+ on CsPb(Br/Cl) 3 QD surface, which was confirmed by FTIR and XPS analysis. Oxa 2− passivated QDs (Oxa-QDs) exhibited improved photoluminescence quantum yield (PLQY) and enhanced water-resistance stability compared to pristine QDs. For example, after soaking in water–acetone co-solvent for 1 h, Oxa-QDs can maintain the initial cubic morphology and 43.9% of initial PL intensity, while the morphology and luminescence of pristine QDs are almost damaged. Based on the above concept, the Oxa-QD-based QLED presented a maximum external quantum efficiency (EQE) of 4.0%, and operational lifetime (T 50 ) of 84 s, which was a 5-fold enhancement in EQE, and 7-fold enhancement in stability compared to pristine QLED, respectively. Besides, the Oxa-QD-based QLED exhibits better stability in high-humidity air. To sum up, the Oxa 2− passivation strategy has significantly improved the efficiency and water-resistant stability of QDs and devices and would rapidly promote the development of blue-emitting QDs.
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
高影响因子
Light-Science & Applications
·
2025
·Vol. 14
·期 1
·1-8
·
IF 23.4
Jing Yuyu,Yao Mingyu,Yang Min,Li Menglin,Ding He,Yang Gaoling,Zhang Rongjian,Han Dengbao,Liu Huan,Zhong Haizheng
Microdisplay panels are critical components for metaverse technology. Aiming to achieve high-resolution and full-color microdisplay, we report the photolithographic fabrication of color-converted Micro-quantum dot light emitting diodes (QLED) panel by combining blue Micro-QLED electroluminescence (EL) device and red-green quantum dot color converter (QDCC). Pre-patterned templates were firstly photolithographically fabricated and then applied as substrate to fabricate patterned blue Micro-QLED device, achieving an ultra-high pixel resolution up to 6350 pixels per inch (pixel size ranging from 20 μm × 20 μm to 2 μm × 2 μm). Notably, the patterned blue devices achieve a peak external quantum efficiency (EQE) of 7.8% and a maximum brightness of 39,472 cd m −2 . The patterned red devices achieve a peak EQE of 18% and a maximum brightness of 103,022 cd m −2 . By integrating a dual-color red and green QDCC arrays on the top of the blue Micro-QLED, a prototype full-color Micro-QLED panel was fabricated, achieving a resolution up to 1184 pixels per inch with a peak EQE 4.8%, and a maximum brightness of 10 065 cd m −2 . The photolithographic fabrication of color-converted Micro-QLED provides an easy-operated method for achieving cost-effective microdisplay panels.
研究领域:
材料科学
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纳米技术
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光电子学
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显示技术
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半导体器件
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薄膜工艺
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微纳加工
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ORGANIC ELECTRONICS
·
2020
·
IF 3.31
Rongmei Yu,Furong Yin,Chunying Pu,Haizhen Song,Xiumei Xu,Han Zhang,Wenyu Ji
Although much effort has been made to the cadmium-free quantum dot light emitting diodes (QLEDs), it is still a big challenge to achieve an efficient eco-friendly QLED. Here, an extremely efficient QLED based on Ag–In–Zn–S QDs is constructed with the insertion of an 1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBi) hole-spacing interlayer. The electrical properties of single carrier devices demonstrate the TPBi blocks the hole injection, leading to a more balanced charge injection in the device. Transient electroluminescence measurements confirm that the hole accumulation adjacent QDs is dramatically suppressed after the insertion of TPBi, hence limiting the interactions between excitons and holes. Consequently, the peak current (power) efficiency of 6.0 cd/A (6.5 lm/W) is achieved. To the best of our knowledge, this is the record efficiency for the Ag–In–Zn–S QLEDs reported to date. We anticipate this work will provide a new route for optimizing the performance of Cd-free QLEDs.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Yanfu Wan,Chunyan Yang,Xingquan Zhu,Xinyu Zhang,Junfeng Tong,Jianfeng Li,Zhilong Qian,Xiang Ma,Heng Zhang
PEDOT:PSS is widely employed as a hole injection layer (HIL) in quantum dot light-emitting diodes (QLEDs). However, its hygroscopicity and acidity can lead to electrode corrosion and compromise device stability. Here, high-performance HIL-free QLEDs are demonstrated, enabled by carbazole-based self-assembled monolayers (SAMs) functioning as an interfacial modification layer (IML) on ITO. The SAMs boost ITO work function for direct hole injection and use shallow low unoccupied molecular orbital level (LUMO) to curb leakage. Consequently, the QLED incorporating 2-(9H-carbazol-9-yl)ethyl phosphonic acid (2PACz) IML achieves high external quantum efficiency (EQE) of 31.33%, an excellent brightness of 430 900 cd m − 2 and a long T 95 operational lifetime of 5971 h at 1000 cd m −2 , all of which significantly outperforming the PEDOT:PSS device. To the best of the knowledge, these performances are the highest ever reported for HIL-free QLEDs. Furthermore, the 2PACz-based QLEDs can also sustain high EQE (≈20%) at extremely low current densities of 0.015 mA cm −2 (3.6 cd m − 2 ), which is very beneficial for displays to achieve high efficiency at low brightness. This work paves the way for stabler, high-performance QLEDs and faster commercialization.
研究领域:
材料科学
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光电子学
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纳米技术
·
器件物理
·
量子点
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Tianhong Zhou,Shuming Chen
Quantum dot light-emitting diodes (QLEDs) exhibit pronounced thermal- and size-dependent charge injection, characterized by significantly enhanced current under elevated temperatures and reduce device areas. In this study, the underlying mechanisms are elucidated by examining the influence of thermal energy on carrier transport dynamics. This analysis reveals that hole transport is governed by a hopping mechanism, leading to markedly increased hole mobility at higher temperatures, which is a primary contributor to the thermal-dependent current enhancement. This improved hole injection promotes better charge balance and increase luminance. Furthermore, both thermal effect and lateral resistance is identified as key contributors to the size-dependent current behavior. Smaller-area QLEDs exhibit reduced lateral resistance and more pronounced thermal effect, resulting in higher current injection. By leveraging these thermally and geometrically enhanced hole injection characteristics, the application of QLEDs is demonstrated as multi-dimensional visual temperature sensors and realize significantly stronger emission from high-energy excitonic state (1P) transitions in small-area devices.
研究领域:
光电子学
·
纳米技术
·
量子点
·
半导体器件
·
电子器件中的热效应
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2022
·Vol. 18
·期 19
·2200740
·
IF 15.153
Yuhao Geng,Jiazhuang Guo,Huiqing Wang,Si Da Ling,Zhuo Chen,Su Chen,Jianhong Xu
Cesium lead halide perovskite nanocrystals (CLHP NCs) have a wide range of potential applications benefited from the properties of high photoluminescence quantum yield (PLQY), wide luminous gamut, and narrow half peak width. However, due to the ionic nature and sensitivity to moisture, oxygen, or heat, perovskite nanocrystals are too fragile to maintain their crystal structure and optical properties. This work proposes solutions to two key issues in the development of CLHP NCs. First, a productive droplet-based microreactor system is designed to accomplish the scale-up production of CLHP NCs, obtaining sub-gram high-purity nanocrystal powders in a single production process. Second, CLHP NCs which are stable in polar solvents, air environment, and high temperature by using 3-aminopropyl triethoxysilane (APTES) as basic ligand are obtained. Wrapped with Si–O–Si generated by APTES, the CLHP NCs exhibit a longer fluorescence lifetime and higher quantum yield. Especially, the PLQY of CsPbBr 3 @APTES can be stable at higher than 90% for more than 10 days. The Si–O–Si protective layer can also suppress the anion exchange between CsPbBr 3 and CsPbI 3 , maintaining the monochromaticity of nanocrystal luminescence. Eventually, full-spectrum quantum light-emitting diode (QLED) beads with robust nanocrystals are fabricated. The gamut of CsPbX 3 @APTES encompasses 140% of the NTSC color gamut standard.
研究领域:
材料科学
·
纳米技术
·
光电技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）